Effect of gastrin on gastric myo-electric activity

Abstract

In each of 9 dogs, eight electrodes were implanted serially from the fundus to the pylorus on the anterior serosal surface of the stomach. After recovery, the effect of a gastrin pentapeptide and synthetic human gastrin I on the pattern of electric activity was determined. Both hormones given subcutaneously (2.5 μg/kg) had similar effects. They increased the mean frequency of the gastric pacesetter potential (PP) from 5.2 to 6.0 cycles/min. These hormones also increased the mean incidence of bursts of action potentials associated with cycles of the antral PP from 10 to 86%, but they did not consistently alter the velocity of PP propagation in the corpus (0.3 cm/sec) or antrum (1.7 cm/sec). The duration of the bursts of action potentials, 10 min after gastrin pentapeptide, was approximately 4 sec both in the corpus and in the antrum, but the width of the caudally progressing band of action potentials was greater in the antrum (3–6 cm) than in the corpus (less than 3 cm). The onset of changes in the pattern of electric activity occurred within 2 min after an intravenous infusion of gastrin pentapeptide (0.1 μg/kg/min) was started, and the effects began to subside between 3 and 5 minutes after the intravenous infusion was stopped. Gastrin appears to enhance gastric motility through specific effects on gastric electric activity.